1. Field of the Invention
The present invention relates to a razor blade sharpener; more particularly to a disposable razor blade sharpener that sharpens multiple blades in a cartridge at the same time
2. Description of the Prior Art
Many patents address issues related to sharpening razor blades and some address sharpening razor blades with multiple cutting blade edges. The disposable razor blades with multiple cutting edges are generally sharpened from only one side, unlike double-edged razor blades wherein the cutting edge is formed by sharpening upper and lower surfaces and the cutting edge is the intersection of these two sharpened surfaces.
U.S. Pat. No. 1,540,078 to Long discloses a sharpener. A single edged Gillette safety razor blade is sharpened. The safety razor blade is secured to a metal handle and stropped over a pair of corrugated inclined metallic strips attached to a wooden block. Sliding motion sharpens the safety razor blade edge. Stropping or honing of the razor blade edge over corrugated metal manually destroys the edge rather than sharpening it since the single edge safety razor blade is hard. The device does not sharpen a blade edge automatically and has no means to sharpen multiple edge disposable razor blade cartridges.
U.S. Pat. No. 1,588,322 to McAdoo discloses a razor blade sharpener without the use of a strop or hone. A magnetized holder is used to act on the extremely fine sensitive cutting edge of a razor blade and return it to its normal position. The blade edge is not sharpened, but rather the magnetic forces are used to bring the edge back to its normal position. This device can only act on blades which are magnetizable, like the Gillette single edge blue blades. The disclosed a razor blade sharpener cannot accommodate multiple edge blades.
U.S. Pat. No. 2,289,062 to Muros discloses a safety razor receptacle. A frictionally retained double-edged blade is pivotally mounted to a blade holder. Two stropping rollers sharpen the edge of the blade as they are manually rotated by turning a crank handle. This blade-sharpening device is only capable of sharpening double sided blades and not multiple edge blades, and especially not blades which are mounted in a cartridge. Furthermore, the operation of the device is manual, not automatic.
U.S. Pat. No. 2,458,257 to Donovan discloses a safety razor blade sharpener. A double-sided safety razor blade is slid against a substantially flat abrading surface ensuring intimate contact of the entire cutting edge. Such a device is operable for sharpening a double-sided blade, not a multiple edge blade; it is not capable of handling blade cartridges. Moreover, the sharpening operation is manual, not automatic.
U.S. Pat. No. 3,854,251 to Paule discloses a sharpening device for cutting implements such as razor blades. The sharpening device employs a vibrating unit to reciprocate the blade to be sharpened between a series of honing elements, which are spring load biased. The honing cylinders may be removed and rotated to expose fresh honing surface to the blade edge that is being sharpened. This is an automatic honing apparatus for a double-sided blade using cylindrical honing stones and vibratory movement. There is no provision for sharpening a safety razor blade with multiple edges, especially blades which are mounted in a cartridge.
U.S. Pat. No. 3,875,702 to Yacos discloses a blade sharpening mechanism. Two sharpening stones are mounted on a flexible frame which is subjected to reciprocating or vibratory movement by a motor driven cam. When the shaft is rotated in one direction, one edge of the blade is engaged against the stone, while rotating the shaft in the opposite direction engages the opposite edge of the blade against the stone. It is capable of sharpening a double-sided safety razor blade by pressing one edge against a vibrating or reciprocating stone. The opposite side of the same edge is polished when a shaft is rotated to contact the opposite side of the edge against another vibrating or reciprocating stone. This device is incapable of sharpening multiple edge blades, especially blades which are mounted in a cartridge and requires sharpening from one side only.
U.S. Pat. No. 5,036,731 to Fletcher discloses a razor-sharpening device. This razor blade sharpening device includes a sharpening member, a housing for securing the sharpening member therein and mechanism for manually guiding a razor blade in back-and-forth sharpening movement within the housing. The housing has a transverse slot for inserting a head of a razor blade holder, and a longitudinal slot in a top plate thereof for linear movement therein of the handle, which carries the blade holder. The sharpening or honing member is made of a plate of glass secured to the bottom wall of the housing. There are no moving parts within the sharpening device and all sharpening movement is provided by the user moving the handle securing the razor blade. The device requires manual operation whereby the user must slide a razor blade over the hard surface anchored to the bottom of the device. There is no indication that this device can be used for multiple edge cartridge blades.
U.S. Pat. No. 5,224,302 to Grossi discloses a device for re-conditioning cutting elements of disposable double-blade shavers. The device for re-conditioning the cutting elements of disposable double-blade shavers includes a supporting structure having guides for directing manual sharpening of the blades. The device also includes abrasive elastic material portions fixed to the structure. Re-conditioning of the blades is obtained by providing friction between the blades and the sharpening surfaces. The device is for re-conditioning cutting elements of disposable double-blade shavers. The double edge blade is manually sharpened by the two abrasive elements attached to the T shaped device. This device does not automatically sharpen multiple edged safety razor blades.
U.S. Pat. No. 6,062,970 to Back (hereinafter, the “'970 patent”) discloses a stropping device of a blade for safety razors. The stropping device consists of a main body and an adhesive sheet attached on the back surface of the main body. A guide groove part is longitudinally formed on a front portion of the main body, while a protrusion is integrally and horizontally formed on a top portion of the main body. A stropping plate member, produced from a leather material such as a natural or synthetic leather or suede, is attached on the bottom surface of the guide groove part by an adhesive means. The multiple edge razor is moved manually by the user against a stopping leather in order to sharpen a razor blade. No disclosure is contained by the '970 patent concerning an automatic razor blade sharpening device.
U.S. Pat. No. 6,488,834 to Francis discloses a blade re-sharpener and method. The razor blade sharpener utilizes the principles of an electrochemical cell. The blade forms an anode (−) and a cathodic plate provided in close proximity to the razor edge to be sharpened. The blade tip edge is sharpened electrochemically to provide a fresh, or “as new” razor blade. The blade sharpener has additional uses for sharpening, for example, kitchen knifes and surgical blades. The current source is an external source of current, such as a solar cell, battery or D.C. power supply. The cathodic plate is stainless steel or a conductive plastic, or nickel-plated copper or solid nickel. The electrolyte is a weak solution of sulphuric acid, which will also function as a descaler. The sterilizing substance could be sodium hypochloride. In fact, most ionic solutions will work as the electrolyte equally as well as sulphuric acid. By using a saturated saline solution for the ionic conductor, a safer cell is provided. Two cathodic plates could be provided to sharpen a blade, such as a kitchen knife on two sides thereof. Preferably, the current source would be controlled to switch from one plate to the other. In this device, the electrolytic cell has ionic conducting solutions such as weak sulfuric acid, saturated saline solution, etc., and the blade being sharpened is made as an anode. Passage of electrical current dissolves the anode, presumably sharpening the blade. Since stainless steel razor blades, which are almost universally used, have a protective oxide layer, the passage of current is expected to produce pits in the razor blade rather than sharpening it uniformly. In addition, electrical contact has to be made with the razor blade, which may be difficult in a blade cartridge.
U.S. Pat. No. 6,506,106 to Fletcher discloses an automated razor-sharpening device.
This apparatus for sharpening a razor blade comprises a motor actuated sharpening member mounted in a housing with a slot for receiving the razor head and a cradle assembly for engaging the distal end of the razor handle to hold the razor head in the slot. A carriage assembly holds the sharpening member opposite to the slot with its sharpening surface engaging the cutting edge of a razor blade secured in the razor head. A drive assembly, driven by a motor operated by a timing circuit, causes a repetitive movement of the sharpening surface for a predetermined period of time. The electric drive system of the sharpener comprises a small electric motor and a reduction gear assembly. The reduction gear assembly drives a cam assembly arranged to slidingly oscillate back and forth a carriage on which is mounted a rectangular strip or slide of mildly abrasive material. This mildly abrasive material may be a hard vitreous material such as, for example, glass, porcelain, or a ceramic. Testing of the motorized sharpening device indicates that the useful life of typical hand-held razors, such as a GILLETTE, SCHICK and BIC, may be extended from about 10 to about 150 shaves, or about 1500%. In this automated razor-sharpening device, the dual edged blade is made to engage with an abrasive slide, which is rigid and oscillated by a cam and motor drive. Since this overall arrangement is rigid, any slight misalignment in the positioning of the razor blade results in complete loss of razor edge. This limitation becomes even more serious when two or more razor blades in a disposable razor cartridge are located side by side and contact the oscillating abrasive slide. Moreover, the disclosure does not provide a way to determine when the blade edges are adequately sharpened.
Foreign Patent No. EP 393512 to Lepar discloses a device for honing razor blades, with the emphasis being placed upon twin-bladed razors. It was found that detritus tends to accumulate and eventually clog the space between the blades and this contributes to the rapid degradation of the blade and generally to an unhygienic state of affairs. The device for honing razor blades aims to provide a means of enhancing the blade life, and at the same time brings a welcome improvement in blade hygiene. A header chamber receives the water and there is an opening in a common wall between the shroud and the chamber for passage of the water to the blade(s) of the mounted razor. The principle of operation of the device is essentially similar to that which will enable the constant dripping of water to wear away a stone. In shaving, the blades are always drawn across the skin in a uniform direction and this tends to cause the very keen edge of the blades to be slowly bent back until the cutting angle of the blades has been so altered that the blade now feels blunt. By passing a stream of water over the blades in the opposite direction, and particularly when under reasonable pressure, the very keen edge is gently bent back to the correct angle. Repeated use of the apparatus of the invention will keep this cutting edge properly aligned and honed for a considerable period of time. This patented device cleans accumulated debris between blades by use of high-pressure water. The rapid movement of water is said to deform the blade edge in a direction that is opposed to shaving thereby straightening out any blade edge deformation caused by shaving. Since very high flow rates are needed to apply adequate force, it is unlikely that the blade edges are brought back to their original geometry.
Reference ModernGent.com at http://www.moderngent.com/site/razormatel.php on the Internet discloses a shaving kit addition. By placing the razors blade edge on the RazorMate's scientifically positioned force field the edge is straightened by magnetostriction after each shave. The blade is also shielded from rusting and pitting between shaves. The RazorMate increases the life of any disposable razor blade. It even improves new blades by straightening and reducing the number of irregularities that occur in the factory. RazorMate takes up very little space being about the same size as a TV remote. Permanent ceramic magnets mean there is no maintenance needed. Just place your razor on the RazorMate and leave it there till you next shave. RazorMate makes your blade last significantly longer saving you money and cutting down on waste so it is also eco-friendly. The device uses ceramic permanent magnets, which has a low ‘energy product’ and therefore precludes application of strong magnetic fields. It is therefore unlikely that any razor edge is straightened by the device.
There remains a need in the art for a reliable, disposable multiple edge razor blade sharpening device that automatically sharpens the razor blade edges and indicates when the sharpening operation is complete.